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fortesama
2011-12-08, 08:13 AM
Not sure where to post this. Move this to the appropriate section thank you.

As part of my IT college project we're supposed to code a text based rpg. nothing too fancy needed and the system i've implemented a system loosely based on dnd 3.5 for generating PC and enemy stats and i'm planning to use it's psion as a base for the spellcasting system, using it's pp values to determine base maximum mp.

Thing is, i can't figure out what formula was used to generate those numbers. Anyone have any idea on what was used? Or can anyone figure out a formula close to it? I've been playing around with numbers to no avail.

Further details of the system i used will be posted on request.

Yora
2011-12-08, 08:22 AM
It's actually very easy.

1st level: 0+2 = 2
2nd level: 0+2+4 = 6
3rd level: 0+2+4+5 = 11
4th level: 0+2+4+5+6 = 17
5th level: 0+2+4+5+6+8 = 24
6th level: 0+2+4+5+6+8+10 = 35
7th level: 0+2+4+5+6+8+10+11 = 46
8th level: 0+2+4+5+6+8+10+11+12 = 58
...

Problem is, that the line does not seem to be completely regular. But for your own game, you could use a system in which the increase is perfectly linear to the character level.

For example "PP = (PP for level-1 ) + level"

Bonus PP are even easier, if you want to use them:
"(Ability modifier / 2) * Class level"

supermonkeyjoe
2011-12-08, 09:03 AM
5th level: 0+2+4+5+6+8 = 25

corrected

The psion PP progression is... unusual, it's certainly not a linear progression so you can either hard-code in the values or just make up your own numbers that are a function of level.

fortesama
2011-12-08, 09:09 AM
It's actually very easy.

1st level: 0+2 = 2
2nd level: 0+2+4 = 6
3rd level: 0+2+4+5 = 11
4th level: 0+2+4+5+6 = 17
5th level: 0+2+4+5+6+8 = 24
6th level: 0+2+4+5+6+8+10 = 35
7th level: 0+2+4+5+6+8+10+11 = 46
8th level: 0+2+4+5+6+8+10+11+12 = 58
...

Problem is, that the line does not seem to be completely regular. But for your own game, you could use a system in which the increase is perfectly linear to the character level.

For example "PP = (PP for level-1 ) + level"

Bonus PP are even easier, if you want to use them:
"(Ability modifier / 2) * Class level"

so... if i understood this correctly, the calculations should come out like this:
level 1 = 1+1=2
level 2 = 2-1 +2 = 3
level 3 = 3-1 +3 = 5
level 4 = 5-1 + 4 = 8
level 5 = 8 -1 + 5 = 12
level 6 = 12-1 + 6 = 17
...

I'll think up of an algorithm later and i'll have to adjust the scaling for various spell augmentations. Any suggestions for rolling damage spells? I'm currently using 1d6 per pp spent. To put this into perspective, hp growth isn't too different from dnd 3.5. Combat is 1v1 and yes, using save-or-die/suck is also a perfectly viable tactic here instead of straight up damage... which would make encounters with enemy spellcasters particularly dangerous but that's kind of the point for this game. :smallbiggrin:

The_Ditto
2011-12-08, 09:44 AM
I tried to come up with a formula for this a while back, but best I got was a complex polynomial that never quite nailed it:

y = -3E-05x5 + 0.0012x4 - 0.006x3 + 0.6979x2 + 1.6275x - 0.2181

I suppose you could keep going, (hint, use Excel), but it's messy.

As I was in Excel, I just used a lookup table, simpler, easier, more accurate.

Not sure what you need it for, but if possible, just use a lookup. :smallsmile:

As for bonus PP;

(Ability Mod * Level ) / 2
(IIRC ... :smallwink: )

fortesama
2011-12-08, 10:03 AM
I tried to come up with a formula for this a while back, but best I got was a complex polynomial that never quite nailed it:

y = -3E-05x5 + 0.0012x4 - 0.006x3 + 0.6979x2 + 1.6275x - 0.2181

I suppose you could keep going, (hint, use Excel), but it's messy.

As I was in Excel, I just used a lookup table, simpler, easier, more accurate.

Not sure what you need it for, but if possible, just use a lookup. :smallsmile:

As for bonus PP;

(Ability Mod * Level ) / 2
(IIRC ... :smallwink: )

it's in the srd. that's about right. now if i can only test that the current scaling i have for nuke spells won't be too much. also, do any of the 3.5 books have info on stats for guns? i think a friend of mine said there's one somewhere in the dmg.

Jeraa
2011-12-08, 01:01 PM
Guns are on page 145 of the 3.5 DMG. Unfortunately, that section doesn't seem to have been made Open Content, so you won't find it in the SRD.

The_Ditto
2011-12-08, 04:25 PM
Just thinking, a much simpler "formula", if you are looking to do your own system - might work, or you could "fudge it" as needed:

Given a character's Level: Level
Determine Highest level Power known: MaxP = Int ( ( Level + 1 ) / 2 )
(Int = Integer = Floor, depending on your knowledge or language used).
Determine PP cost of highest level power known: MaxPP = ( MaxP * 2 ) - 1

Current PP @ Level = ( PP @ ( Level - 1 ) ) + MaxPP + Level

Gives a rough parallel of the 3.5 progression. (ends with more at level 20, but that isn't a big deal if you're trying to encourage players not to nova+rest tactic :smallwink:)

fortesama
2011-12-08, 11:45 PM
Just thinking, a much simpler "formula", if you are looking to do your own system - might work, or you could "fudge it" as needed:

Given a character's Level: Level
Determine Highest level Power known: MaxP = Int ( ( Level + 1 ) / 2 )
(Int = Integer = Floor, depending on your knowledge or language used).
Determine PP cost of highest level power known: MaxPP = ( MaxP * 2 ) - 1

Current PP @ Level = ( PP @ ( Level - 1 ) ) + MaxPP + Level

Gives a rough parallel of the 3.5 progression. (ends with more at level 20, but that isn't a big deal if you're trying to encourage players not to nova+rest tactic :smallwink:)

This could work... although PP restoration items do exist in this game, though only as a fairly rare random items. Going nova then resting won't work quite well with what i'm planning though.